hcl/zcl/zclsyntax/navigation.go
Martin Atkins c9c2a2bd16 zclsyntax: Implement the ContextString interface on our Nav
This allows tooling to get a string describing the context of a particular
offset into the file. This is used, for example, to provide context
above the source code snippets in console-printed diagnostic messages.
2017-06-04 09:52:16 -07:00

42 lines
745 B
Go

package zclsyntax
import (
"bytes"
"fmt"
)
type navigation struct {
root *Body
}
// Implementation of zcled.ContextString
func (n navigation) ContextString(offset int) string {
// We will walk our top-level blocks until we find one that contains
// the given offset, and then construct a representation of the header
// of the block.
var block *Block
for _, candidate := range n.root.Blocks {
if candidate.Range().ContainsOffset(offset) {
block = candidate
break
}
}
if block == nil {
return ""
}
if len(block.Labels) == 0 {
// Easy case!
return block.Type
}
buf := &bytes.Buffer{}
buf.WriteString(block.Type)
for _, label := range block.Labels {
fmt.Fprintf(buf, " %q", label)
}
return buf.String()
}